But even by using these resolutions, it is pointless if I set it at 72dpi, as I will still have possibly very detailed graphics (that is the main thing, I don't want detailed graphics, I want to go pixelated).

I figured it might be related to the sprite size limit, i.e.:

Sprites can be 8 × 8, 16 × 16, 32 × 32, or 64 × 64 pixels, each using
one of eight 16-color palettes and tiles from one of two blocks of 256
in VRAM. Up to 32 sprites and 34 8 × 8 sprite tiles may appear on any
one line.

This would work for sprites (characters, objects), but what about maps? Are they built entirely from 8x8 tiles? And then, at what resolution is the end result displayed?

It might seem like I am giving the question and answers at the same time, but all of these are suppositions I am making, so could someone confirm or correct them?

The DPI you use for the background tiles should be the same as the DPI you use for the sprites. But the actual DPI shouldn't much matter, don't worry about it -- if you're going to mimic the resolution of the system exactly, you will get detailed-looking sprites at that resolution on a modern monitor. They'll just be extremely small. You'll want to scale everything up anyway if you want to consume a reasonable amount of space on the screen. Probably with nearest-neighbor or simple bi-linear filtering.

In addition to the resolution and pallet limitations a lot of what made the NES experience different from modern gaming is the old CRT screens NES games were displayed on. So if you really want to capture that retro feel, I suggest using a shader that mimics the inaccuracies of these old displays.

The effect I am going for is more about the game design/feel, maybe not up to the screen aspect :) Like what you get using an emulator for example. But thanks for the idea, it might actually get useful
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Cristol.GdMMar 21 '12 at 23:06